Split Rings, Grooving Tools, and Spike Grids

Split Ring Timber Connectors

Split rings Split rings

Available in 2-1/2″ and 4″ diameters, split rings are used primarily in the assembly of clear span wood trusses for spans ranging from 20′ to 250′. Placed in specially made grooves in overlapping members, the rings develop maximum strength in the joints by distributing the stress over a greater area. The Split Ring provides for a tight-fitting joint when the ring is fully seated in the conforming groove. Generally, the 2-1/2″ diameter ring is used for lighter trusses and trussed rafters utilizing 2″ lumber; the 4″ diameter ring is used for heavier trusses using 3″ and heavier material.

Split Ring Dimensions

Bolt Diameter Inside Diameter Depth Lumber Minimum Dimension Weight Per 100 Pieces Part Numbers
Ring In 1 Face Ring In Both Faces Plain Galvanized Plain Galvanized
12 212 34 1 x 312 112 x 312 27 28 18683 18684
34 4 1 1 x 512 112 x 512 68 70 18685 18686

Grooving Tools for Split Rings


A complete grooving tool consists of a cutter head and a pilot. The pilot is divided (for descriptive purposes) into three parts: the “shank” is the upper part, the “shaft” (sometimes called the hub) is the central part, and the “pilot” is the lower part. The shank fits into the chuck of a drill; the shaft fits into a hole in the cutter head; the pilot goes into a previously bored hole in the timber, which positively centers the ring.

Grooving Tool Sizes

Tool Number Split Ring Size Grooving Tool Part Number Replacement Blade Part Number
301 / TSR64 212" 18644 18649
302 / TSR102 4" 18645 18651

Spike Grids

Flat Spike Grid Curved Spike Grid

Spike grid timber connectors are engineered to enhance joint strength and rigidity while at the same time simplifying assembly procedures. Timber structures in which spike grid connectors are utilized include decks, pole frame buildings, pilings, wharves, and bridges or trestles. They are also used to advantage in the construction of pole-supported “building platforms” for conventional building of homes, resort buildings and other structures situated on hillsides as well as over or near water. Flat spike grids are used between sawn timbers, while single curved spike grids are used between round piles or poles and sawn members. Spike grids are manufactured from malleable iron in accordance with ASTM A47 grade 32510.

Spike Grid Dimensions

Type Part Number Finish Size Depth Bolt Hole Dia. Bolt Dia. Max Lumber Min. Dimensions
Grid in One Face Grid in Both Face
Flat 18687 Black 4-1/8" x 4-1/8" 1" 1.06" 1" 1-5/8" x 5-1/2" 2-5/8" x 5-1/2"
18688 Galv
Single Curve 18681 Black 4-1/8" x 4-1/8" 1.38" 1.06" 1" 1-5/8" x 5-1/2" --
18682 Galv